playing movies on psp

I downloaded an mp4 movie for my psp but it doesnt play.ive created all the folders you need and still nothing.i know somthing is on the memory stick cause it takes memory away.what am i doing wrong?i have version 3.8

I tried that still nothing. i dont understand, from the stuff that i have read it seems so easy to put movies on the psp.the next thing im going to try is the video 9, and covert it myself.what do you think?

I tried that still nothing. i dont understand, from the stuff that i have read it seems so easy to put movies on the psp.the next thing im going to try is the video 9, and covert it myself.what do you think?